脆性组氨酸三联体基因蛋白在直肠癌组织中的表达及其与细胞凋亡的相关性研究

目的探讨脆性组氨酸三联体基因蛋白(FHIT)在直肠癌组织中的表达情况及其与细胞凋亡间的关系。方法利用组织芯片和免疫组织化学技术,检测16例正常直肠和16例腺瘤组织标本及80例直肠癌组织中的FHIT、Bax、Bcl-2和survivin基因蛋白的表达,并运用脱氧核糖核苷酸末端转移酶介导的缺口末端标记技术(TUNEL)检测直肠癌细胞凋亡。结果(1)直肠癌组织FHIT蛋白异常表达率为53.8%(43/80),其表达减弱与患者年龄、性别及肿瘤组织分型无关(P>0.05);而与肿瘤Dukes分期、淋巴结转移和患者的5年生存率关系密切(P<0.05,P<0.01)。(2)Bax、Bcl-2和survivin在直肠癌组织中的表达率分别为72.5%、51.3%和77.5%;survivin蛋白高表达与FHIT蛋白低表达密切相关(P<0.05);FHIT蛋白表达下降的同时,Bcl-2上调及Bax下调(P<0.01)。(3)FHIT蛋白表达减弱时细胞凋亡指数(AI)也下降;FHIT蛋白不同表达组间的AI比较,P<0.01。结论FHIT基因表达下降可能与直肠癌的发生密切相关,FHIT基因可能参与肿瘤细胞凋亡的调节。

Fragile histidine triad protein expression and correlation with apoptosis in rectal carcinoma

Objective To investigate the relationship between the expression of fragile histidine triad(FHIT)protein and the clinicopathological characteristics of rectal carcinoma.The relationship between FHIT protein expression and Bcl-2,Bax and survivin expression,as well as cell apoptosis in rectal carcinoma were explored.Methods Tissue microarray and immunohistochemistry SP were used to detect the expression of FHIT,Bcl-2,Bax and Survivin in 16 cases of normal rectal tissue,16 cases of rectal adenoma and 80 cases of rectal carcinoma.TUNEL was used to detect apoptosis index(AI)in 80 cases of rectal carcinoma.Results The positive rates of FHIT expression in normal rectal tissue,rectal adenoma and adenocarcinoma were 93.8%,75.0% and 46.3% respectively.There were no significant differences between FHIT expression and histological types,gender and age(P>0.05).FHIT expression was significantly corelated with lymph node metastasis,Duke's stage and 5-year survival rate.The expression of FHIT was positively correlated with that of Bcl-2,Bax and survivin in rectal cancer.The mean AI in FHIT-negative tumors was significantly lower than that in FHIT-positive tumors(P<0.01).Conclusions The reduction of FHIT protein expression may play an important role in the development of rectal carcinoma,and FHIT protein may be associated with the regulation of cell apoptosis.